Currently, in the field of regenerative medicine, studies in which stem cells collected from a subject are caused to proliferate or differentiate ex vivo, and are thereafter transplanted into a subject, thereby promoting regeneration of tissue of the subject, have been carried out.
In ex vivo cultural proliferation of stem cells, adding serum to the medium is known to improve culture efficiency.
As a method of preparing such serum, a method in which a blood collection tube is used that contains a blood coagulation accelerating solid, such as glass powder, is disclosed in Japanese Unexamined Patent Application Publication No. 2000-000228 (Patent Document 1). In addition, a method in which: platelets are activated by bringing collected blood into contact with a blood coagulation accelerating solid such as glass beads; cell growth factors are released; and then serum is separated, is disclosed in Japanese Patent No. 3788479 (Patent Document 2).